import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.Serializable;

import javax.swing.ComboBoxEditor;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.ListCellRenderer;
import javax.swing.event.EventListenerList;

 public class ColorComboBox {
  static class ColorCellRenderer implements ListCellRenderer,Serializable {
    /**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	protected DefaultListCellRenderer defaultRenderer = new DefaultListCellRenderer();

    // width doesn't matter as combobox will size
    private final static Dimension preferredSize = new Dimension(0, 20);

    public Component getListCellRendererComponent(JList list, Object value,
        int index, boolean isSelected, boolean cellHasFocus) {
      JLabel renderer = (JLabel) defaultRenderer
          .getListCellRendererComponent(list, value, index,
              isSelected, cellHasFocus);
      if (value instanceof Color) {
        renderer.setBackground((Color) value);
      }
      renderer.setPreferredSize(preferredSize);
      return renderer;
    }
  }

  public static void main(String args[]) {
    Color colors[] = { Color.black, Color.blue, Color.cyan, Color.darkGray,
        Color.gray, Color.green, Color.lightGray, Color.magenta,
        Color.orange, Color.pink, Color.red, Color.white, Color.yellow };
    JFrame frame = new JFrame("Color JComboBox");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    Container contentPane = frame.getContentPane();

    final JComboBox comboBox = new JComboBox(colors);
    comboBox.setMaximumRowCount(5);
    comboBox.setEditable(true);
    comboBox.setRenderer(new ColorCellRenderer());
    Color color = (Color) comboBox.getSelectedItem();
    ComboBoxEditor editor = new ColorComboBoxEditor(color);
    comboBox.setEditor(editor);
    frame.setLayout(null);
    comboBox.setBounds(20, 20, 300, 20);
    contentPane.add(comboBox);

    final JLabel label = new JLabel();
    label.setOpaque(true);
    label.setBackground((Color) comboBox.getSelectedItem());
    contentPane.add(label, BorderLayout.CENTER);

    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        Color selectedColor = (Color) comboBox.getSelectedItem();
        label.setBackground(selectedColor);
      }
    };
    comboBox.addActionListener(actionListener);

    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}

class ColorComboBoxEditor implements ComboBoxEditor {
  final protected JButton editor;

  transient protected EventListenerList listenerList = new EventListenerList();

  public ColorComboBoxEditor(Color initialColor) {
    editor = new JButton("");
    editor.setBackground(initialColor);
  }

  public void addActionListener(ActionListener l) {
    listenerList.add(ActionListener.class, l);
  }

  public Component getEditorComponent() {
    return editor;
  }

  public Object getItem() {
    return editor.getBackground();
  }

  public void removeActionListener(ActionListener l) {
    listenerList.remove(ActionListener.class, l);
  }

  public void selectAll() {
    // ignore
  }

  public void setItem(Object newValue) {
    if (newValue instanceof Color) {
      Color color = (Color) newValue;
      editor.setBackground(color);
    } else {
      // Try to decode
      try {
        Color color = Color.decode(newValue.toString());
        editor.setBackground(color);
      } catch (NumberFormatException e) {
        // ignore - value unchanged
      }
    }
  }

  protected void fireActionEvent(Color color) {
    Object listeners[] = listenerList.getListenerList();
    for (int i = listeners.length - 2; i >= 0; i -= 2) {
      if (listeners[i] == ActionListener.class) {
        ActionEvent actionEvent = new ActionEvent(editor,
            ActionEvent.ACTION_PERFORMED, color.toString());
        ((ActionListener) listeners[i + 1])
            .actionPerformed(actionEvent);
      }
    }
  }
}

        